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Polyamorous Middle Child Syndrome: Being in the Second Oldest Relationship

Polyamorous Middle Child Syndrome: Being in the Second Oldest Relationship

The Worst of Both Worlds?

“So he let me know that another girl asked him out and he said yes,” she says. “And I want to be happy for him, but…”


“We haven’t been together that long,” she says. “It’s hard with his dating someone new so soon.”

I nod.

“Like, I’m fine with his wife,” she continues. “And this new girl is great, I just… I don’t know. It makes me worry.” She shakes her head. “I bet I sound crazy.”

“Not at all,” I say. “He’s been with his wife a while, hasn’t he?”

“Yeah,” she says.

“So she’s a known quantity. She was there when you showed up. You knew where you stood with her in his life.”

“But this new girl is a complete unknown. She could be a game changer,” she says.

I nod.

“I just feel like it’s the worst of both worlds. Don’t have the commitment or the demonstrated security of the long-standing relationship. And I’m not going to be the new shiny anymore,” she says. “It’s like middle child syndrome.”

Middle Child Syndrome

When Alfred Adler first suggested birth order theory as a way of understanding the development of personality, he identified a phenomenon known as middle child syndrome. Adler asserted that middle children often feel very left out and practically invisible compared to their siblings. Older children make their mark by being the first to accomplish things. And younger children are often babied. But middle children? Get lost in the crowd. They have a harder time feeling special.

And while the scientific validity of birth order theory has been questioned (e.g., see Rohrer, Egloff, & Schmukle, 2015), I’ve definitely seen these kinds of patterns in polyamorous relationship systems.

It can be extra trying when you’re not established as an anchor partner and your love starts to date someone new.


Please see this post for ways to work through feelings of insecurity.

Featured Image: CC BY – Brandon Atkinson